The use of cameras, and in particular of movie cameras, frequently takes place under unfavorable conditions in which the camera lens has to be protected from particles such as raindrops, snowflakes or insects, or the like. Specifically, the camera lens needs to be free of such particles to ensure a sufficient image quality.
It is known to position a fast-rotating glass disk in front of the lens so that all approaching particles stuck to the glass disk are hurled towards the circumference of the disk by the centrifugal force produced when rotating the glass disk. Thus, the particles does not obstruct the lens, so as to maintain image quality.
Such a centrifugal lens protection device is disclosed in U.S. Pat. No. 3,879,742 in which a surveillance camera is located in a weatherproof housing having a rotatable disk.
U.S. Pat. No. 5,223,880 describes a centrifugal lens protection device for protecting the camera lens. The protection device is disk-shaped and operable by a magnetic motor. The protection device is configured to be fastened onto the free end of the lens.
U.S. Pat. No. 5,315,333 discloses a rotating disk attached to the front of a camera housing via carriers.
Another like example of a lens protection device having a rotating disk in front of the lens is disclosed in U.S. Pat. No. 6,731,867.
However, current lens protection devices are not easily attached to camera housings, such as a camera housing commonly referred to in the art as a matte box. Accordingly, substantial, time-consuming conversion work is necessary to change an optical lens attachment such as a filter, when current lens protection devices are mounted within the camera housing.
An example of a matte box for a movie camera is shown in U.S. Pat. No. 4,687,312. The matte box includes a frame configured to attach to the front of the camera lens. The matte box includes a light shade for engaging the camera lens and at least one filter is arranged between the frame and the light shade. The matter box further includes a plurality of filter holding modules having matching dovetail slots disposed on the front and rear surfaces of each filter holding module so as to enable the fast assembly and release of any number of like filter holder modules to the frame. A releasable latching mechanism is provided at each module to hold each module in alignment with the adjacent module.
Another example of a matte box, commonly referred to in the art as a compendium, has a modular structure, and is disclosed in German utility model DE 20 2005 004 067 U1. The compendium includes a base having a base carrier which is connected at one side to a lens hood or sun shade having selectively fixed or pivotable blades. On the other side is an arrangement of a plurality of filter holding modules. Each of the filter holding modules connected to each other via quick-fastening and the plurality of filter holding modules is connected to the lens hood. The number of filter holding modules is determined by how many filter holding modules are desired in the link, and any of the individual filter holding modules can be replaced or can be removed from the base matte box by disconnecting the filter module from the link.
Further developments of these matte boxes are available on the market, with a matte box offered under the trade name “ARRI MB-14” being mentioned only by way of example.